What is the superheating rate?
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What is the superheating rate? What does it represent?
http://202.118.127.66/lnpujpk/lygc/sylzgcwjj/syzl.pdf You can refer to the PDF at the above link; it may help you understand vaporization rate and its characterization.
To ensure the recovery rate, the feed must have a sufficient vaporization fraction in the vaporization section of the oil distillation tower. To ensure a certain amount of liquid-phase reflux in the layers of trays below the lowest side stream, the vaporization rate in the feed section should be slightly higher than the total yield of the products in the upper part of the tower; this excess amount is referred to as the over-vaporization amount. The percentage of the feed amount represented by this over-vaporization amount is known as the over-vaporization rate. The superheating rate of oil distillation columns is generally between 2% and 5%
Taking a atmospheric pressure tower as an example, keeping the superheating rate at 2–3% can help reduce the temperature at the outlet of the atmospheric pressure furnace. Practice has shown that for every 1% increase in the superheating rate, the load on the heating furnace increases by 2%.
That is, after crude oil enters the distillation tower, it undergoes flashing and vaporization in the flashing section; the gas produced is the output from this distillation section. However, to ensure an adequate output volume, the amount of vaporization is slightly higher than the output volume. (Amount of vaporization – Output volume) / Feed volume = Over-vaporization rate